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Removing a list of characters in string
...unicodes), the absolutely best method is str.translate:
>>> chars_to_remove = ['.', '!', '?']
>>> subj = 'A.B!C?'
>>> subj.translate(None, ''.join(chars_to_remove))
'ABC'
Otherwise, there are following options to consider:
A. Iterate the subject char by char, omit unwa...
What is a NullReferenceException, and how do I fix it?
.... This means you either set it to null, or you never set it to anything at all.
Like anything else, null gets passed around. If it is null in method "A", it could be that method "B" passed a null to method "A".
null can have different meanings:
Object variables which are uninitialized and hence poi...
InputStream from a URL
...
Calling this method in UI thread in Android will raise an exception. Do it in a background thread. Use Bolts-Android
– Behrouz.M
Mar 6 '19 at 10:16
...
Cartesian product of x and y array points into single array of 2D points
... 5],
[2, 5],
[3, 5]])
See Using numpy to build an array of all combinations of two arrays for a general solution for computing the Cartesian product of N arrays.
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How do I select a random value from an enumeration?
...
Use Enum.GetValues to retrieve an array of all values. Then select a random array item.
static Random _R = new Random ();
static T RandomEnumValue<T> ()
{
var v = Enum.GetValues (typeof (T));
return (T) v.GetValue (_R.Next(v.Length));
}
Test:
for (in...
Writing a Python list of lists to a csv file
...It kinda makes sense in hindsight, but not informative of where to look at all.
– Rambatino
May 25 '18 at 7:30
...
Bash function to find newest file matching pattern
... Your one liner is giving me right answer, but the "right" way is actually giving me the oldest file. Any idea why?
– NewNameStat
Apr 4 '19 at 21:59
|...
Pretty-print an entire Pandas Series / DataFrame
...: # more options can be specified also
print(df)
This will automatically return the options to their previous values.
If you are working on jupyter-notebook, using display(df) instead of print(df) will use jupyter rich display logic (like so).
...
Declaring an enum within a class
...uct Color
{
enum Type
{
Red, Green, Black
};
Type t_;
Color(Type t) : t_(t) {}
operator Type () const {return t_;}
private:
//prevent automatic conversion for any other built-in types such as bool, int, etc
template<typename T>
operator T () const;
};
...
mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...